I'm glad this thread is back as I had almost forgotten about the Ultra-6 Sun Tours. I installed them on my first good bike in the mid-80's because they were really cheap on the remainder table at Nashbar's Youngstown, OH outlet store and were the only 13x28 6-speed freewheels I could find at the time. They shifted very poorly (maybe the Sedisport chain had something to do with it too) but did have the desired gear range and price.